(a) Field of the Invention
The present invention relates generally to a removal device for electrostatic precipitators and more particularly to a removal device which utilizes scrapers capable of linear displacement to remove particles adhered to the surface of electrostatic plates.
(b) Description of the Prior Art
In conventional electrostatic precipitators which are used in handling oil-containing gases, oil-containing particles attracted to electrostatic plates stick themselves thereto due to their own stickiness after their electric charges are neutralized. After a period of time, a layer of oily scum is formed on the electrostatic plates. If the conventional method of electrostatic precipitation which utilizes vibration or washing is adopted to remove the particles on the electrostatic plates, it will not be effective. The oily scum will not be shaken off the electrostatic plates by vibration. If a detergent is added to help wash away the oily scum from the electrostatic plates, the electrostatic plates have to be completely dried after washing before they may be used again. This washing procedure plus the time spent in allowing the electrostatic plates to dry will take a considerably long time, hence this method is not very feasible in working environments like restaurants which require quick and effective removal of oily dirt and scum.
In the earlier U.S. Pat. application Ser. No. 08/273,797 (filed on Jul. 12, 1994), an electrostatic precipitator has been disclosed, in which a plurality of scrapers are employed to match circular electrostatic plates capable of axial rotation to remove scum on the electrostatic plates. But in this kind of prior precipitators, it is necessary to have either the scrapers or the electrostatic plates to be capable of axial rotation, and the electrostatic plates must be circular in shape. This arrangement is therefore ineffective when applied to current rectangular electrostatic plates. In particular, the scrapers are arranged within the collecting zone so that they may affect the overall collecting effect.